The transmission of high-speed data via cable television systems involves the bi-directional transfer of Internet Protocol (IP) traffic over a cable system, typically an all-coaxial or hybrid fiber-coax (HFC) cable network. More particularly, and with reference to FIG. 1, the transmission path over such a cable system is realized at the head end by a cable-modem-termination system (CMTS) and at each customer location by a cable modem (CM). At the head end (or hub), the interface to the data-over-cable system is known as the cable-modem-termination system network-side interface (CMTS-NSI). At the customer locations, the interface is known as the cable-modem to customer-premises-equipment interface (CMCI). The system functions to transparently transfer IP traffic between these interfaces, including, but not limited to, datagrams, Dynamic Host Configuration Protocol (DHCP), Internet Control Message Protocol (ICMP), and IP group addressing (broadcast and multicast).
As described more fully in co-pending U.S. patent application Ser. No. 09/464,637, entitled Network Station Management System and Method, which is incorporated herein in its entirety, a networking manager is a cable modem management task interacting with the application-layer Internet Protocol (IP) components in order to establish and manage Internet connectivity. These IP components can include:
1. Dynamic Host Configuration Protocol (DHCP) Client
2. Trivial File Transfer Protocol (TFTP) for Configuration Download
3. Time of Day (TOD) Client
4. TFTP for New Software Download
5. Simple Network Management Protocol (SNMP) Agent
Each application-layer component is designed to run as a separate task. Each of these tasks use a messaging system (in this particular case Operating System (OS) provided messaging system) and send data to the networking manager in the body of the messages. This task design also enables the networking manager to perform other cable modem management functions (improving CPU bandwidth utilization) by checking on the application-layer task messages only as needed.
The Operations Support System Interface (OSSI) Management component is designed on the Object Oriented Design concept base. The reason for this is to allow sufficient flexibility to deal with the ever-changing OSSI requirements largely depending on control mechanisms through Management Information Base (MIB) Objects. The cable modem OSSI Client Manager is a task created at boot time. It has its own message queue to receive work from the Application-layer tasks or from the networking manager task and it sends messages to the networking manager task.
Thus, the OSSI subsystem architecture is based on a simplified component object model. Each component in this architecture can act as a server or a client. A server component implements a certain functionality set. It exposes its functionality set through interfaces. An interface is an invariant contract that defines the interaction between the server and the client components. An interface is represented by a set of methods whose signatures (function prototypes) never change but whose implementation may change.
For a client to use methods in a server's interface, a client must be able to access the functions through the interface. Hence, there is a need for a method and architecture that enables rapid and efficient client access to the functions embodied in a server interface.